Every bullet I have made a test round for has run through the side gate and into the mag tube just fine. The issue is with the length from nose to crimp groove, as well as the diameter of the the meplat.
Above where I posted having a dozen different molds, that is only for the 44mag, it doesn't include the others. This in about half of what I cast for that can be seen, the top shelf is mostly, 4, and 6 cavity H&G,
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Here is the issue with the MP Hammer seated in the crimp groove,
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As can be seen the lip of the meplat hits squarely on the bottom of the chamber not allowing it to feed into it. This is due to the length and it CAN be seated deeper to allow it to, but I'm not sure it would hold up in the magazine without being in the groove.
This is the Lee 429-240 next to it for comparison,
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